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// Test that IteratorClose is called when a Generator is abruptly completed by
// Generator.return.
var returnCalled = 0;
function* wrapNoThrow() {
let iter = {
[Symbol.iterator]() {
return this;
},
next() {
return { value: 10, done: false };
},
return() {
returnCalled++;
return {};
}
};
for (const i of iter) {
yield i;
}
}
// Breaking calls Generator.return, which causes the yield above to resume with
// an abrupt completion of kind "return", which then calls
// iter.return.
for (const i of wrapNoThrow()) {
break;
}
assertEq(returnCalled, 1);
function* wrapThrow() {
let iter = {
[Symbol.iterator]() {
return this;
},
next() {
return { value: 10, done: false };
},
return() {
throw 42;
}
};
for (const i of iter) {
yield i;
}
}
// Breaking calls Generator.return, which, like above, calls iter.return. If
// iter.return throws, since the yield is resuming with an abrupt completion of
// kind "return", the newly thrown value takes precedence over returning.
assertThrowsValue(() => {
for (const i of wrapThrow()) {
break;
}
}, 42);
if (typeof reportCompare === "function")
reportCompare(0, 0);